diff --git a/src/Directory.Packages.props b/src/Directory.Packages.props
index fa54c02e52..7dfad2157f 100644
--- a/src/Directory.Packages.props
+++ b/src/Directory.Packages.props
@@ -54,7 +54,7 @@
     <PackageVersion Include="NServiceBus.Transport.SqlServer" Version="9.0.0" />
     <PackageVersion Include="NuGet.Versioning" Version="7.3.0" />
     <PackageVersion Include="NUnit" Version="4.5.1" />
-    <PackageVersion Include="NUnit.Analyzers" Version="4.11.2" />
+    <PackageVersion Include="NUnit.Analyzers" Version="4.12.0" />
     <PackageVersion Include="NUnit3TestAdapter" Version="6.1.0" />
     <PackageVersion Include="OpenTelemetry.Exporter.Console" Version="1.15.0" />
     <PackageVersion Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.15.0" />
diff --git a/src/ServiceControl.Audit.Persistence.InMemory/InMemoryAttachmentsBodyStorage.cs b/src/ServiceControl.Audit.Persistence.InMemory/InMemoryAttachmentsBodyStorage.cs
index b46d3b1fac..d2193c57fe 100644
--- a/src/ServiceControl.Audit.Persistence.InMemory/InMemoryAttachmentsBodyStorage.cs
+++ b/src/ServiceControl.Audit.Persistence.InMemory/InMemoryAttachmentsBodyStorage.cs
@@ -1,5 +1,6 @@
 namespace ServiceControl.Audit.Persistence.InMemory
 {
+    using System;
     using System.Collections.Generic;
     using System.IO;
     using System.Linq;
@@ -60,7 +61,7 @@ public async Task<StreamResult> TryFetch(string bodyId, CancellationToken cancel
                     Stream = new MemoryStream(messageBody.Content),
                     ContentType = messageBody.ContentType,
                     BodySize = messageBody.BodySize,
-                    Etag = string.Empty
+                    Etag = Guid.NewGuid().ToString()
                 });
         }
 
diff --git a/src/ServiceControl.Audit.Persistence.Tests/AuditTests.cs b/src/ServiceControl.Audit.Persistence.Tests/AuditTests.cs
index 9dcffaee85..52f360ae46 100644
--- a/src/ServiceControl.Audit.Persistence.Tests/AuditTests.cs
+++ b/src/ServiceControl.Audit.Persistence.Tests/AuditTests.cs
@@ -101,7 +101,7 @@ public async Task Can_roundtrip_message_body()
                 Assert.That(retrievedMessage.Found, Is.True);
                 Assert.That(retrievedMessage.HasContent, Is.True);
                 Assert.That(retrievedMessage.ContentLength, Is.EqualTo(body.Length));
-                Assert.That(retrievedMessage.ETag, Is.Not.Null.Or.Empty);
+                Assert.That(retrievedMessage.ETag, Is.Not.Null.And.Not.Empty);
                 Assert.That(retrievedMessage.StreamContent, Is.Not.Null);
                 Assert.That(retrievedMessage.ContentType, Is.EqualTo(expectedContentType));
             });